Electric cutout



Jan. 6, 1942.

J, R. TATE ELECTRIC CUTOUT Filed June 12, 1939 tions hereinafterdescribed and illustrated in the Patented Jan. 6, 1942 PATENT OFFICEELECTRIC CUTOUT James R. Tate, Toronto, Ontario, Canada Application June12, 1939, Serial No. 278,629 In Canada June 18, 1938 4 Claims.

This invention relates to tubular electric cutouts of either thetop-pull or bottom-pull type. These cut-outs comprise a tubular body ofporcelain or other suitable insulating material, adjacent each end ofwhich is provided a contact to which the conductor wires are connected.Slidable longitudinally in the housing is an insulating tube having acontact adjacent each end adapted to engage the contacts on the body. Afusible link extends between the contacts on the insulating tube tocomplete the circuit.

The objects of the present invention are to devise an improved method ofsecuring the contacts on the tubular body; to provide improved resilientengaging means between the contact on the body and the correspondingcontact on the insulating tube; to provide improved means for removingthe insulating tube from the body; and to provide improved means forventing the insulating tube for the escape of gase in the event that thefusible linkbreaks while the insulating tube is beingremoved from orreplaced in the body.

I attain my objects by means of the construcaccompanying drawing inwhich Fig. 1 is a vertical section of an expulsion cutout of the "bottompull type;

Fig. 2 a cross section on the line 2--2 in Fig. 1;

Fig. 3 a cross section on the line 3-3 in Fig. 1;

Fig. 4 a plan view of the lower end of the cutout; and

Fig. 5 a perspective view of one of the spring contacts.

In the drawing like numerals of reference indicate corresponding partsin the different figures.

I is the tubular body of the device, preferably made of porcelain andalso preferably externally corrugated above and belo the supportingbracket 2. The interior of the body at each end is provided with aportion of enlarged diameter to provide an annular seat or recess, theseat or recess 3 at the upper end being smaller than the seat or recess4 at the lower end.

On the upper end of the body is mounted an upper contact 5, which formsa cap or closure for the upper end of the body, while at the lower endof the body is mounted an annular lower contact 6. The contacts 5 and 6are preferably formed as brass castings, which abut against the 50respective ends of the body. The contact 5 is provided with a downwardlydirected flange 5, the edge portion of which is bent inwardly to engagein a groove 1 in the body. Similarly the contact 6 is provided with anupwardly directed 55 dotted lines.

flange Ba, the edge portion of which is bent inwardly to engage in agroove 8 adjacent the lower end of the body. To avoid damage to theporcelain body during the bending in operation, a cushion 9 of strandedwire, or other suitable material, is interposed between the material ofthe flange and the bottom of the recess. It will be noted that theflanges 5 and 6 are relatively thin compared to the thickness of themain parts of the contact wall and adjacent the edge where the greatestamount of bending takes place, they are thinned down to almost a knifeedge.

The upper contact 5 is provided with an upwardly directed lug 5 which isdrilled to receive the end of the conductor, the latter being held inplace by set screws H3.

Similarly'the lower contact 6 is provided at one side with a lug 6 whichis drilled to receive the end of the other conductor, the latter beingheld in place by set screws ii.

I2 is the insulating tube, to the upper end of which is secured acontact l3, which is provided with a recess to receive a head I on theend of a fusible link [5. The recess is threaded to receive a plug [6which holds the head I of the fusible link firmly in place.

At the lower end of the insulating tube is a contact I! which isprovided at its lower end with a bell-mouthed extension i8, from which30 projects at one side an arm I9, preferably channel-shaped in crosssectiom Fulcrumed between the flanges of the arm i9 is a lever 26. Onthe pivot pin is arranged a spring 2! normally tending to move th arm tothe position shown in The arm has a hole 22 formed therein adjacent itsfree end through which the fusible link is passed, the end of thefusible link being passed around the pivot pin as shown and secured ontop of the arm by a clamping screw 23.

To facilitate the insertion of the cartridge or insulating tube into thebody, the contact i is provided with a bell-mouthed extension.

The bell-mouthed extension l8 on the contact I1 is for the purpose offacilitating the engagement of a suitable puller stick. The stick isprovided with a head having a coarse thread thereon, as indicated indotted lines in Fig. l, and the interior of the upper part of thebellmouthed extension I8 is correspondingly threaded as shown at 24. Asthere is sometimes danger of the fusible element blowing while thecartridge or insulating tube is being inserted or removed, I providegrooves 25 through the threaded portion of the contact, which groovesprovide convenient escape for gases formed by the blowing of the fuseand thus avoid damage to the cartridge or body.

One of these grooves also provides a channel for the fusible element soas to avoid damaging the latter by the puller stick. Stops 28 areprovided inside the contact 11 to limit the insertion of the pullertrick,

Contact between the body contact and the contact i3 is establishedtherough a resilient member 26 supported in the recess 3 and contactbetween the body contact 6 and the contact I! is established through aresilient member 21 supported in the recess 4. These members 25 and 21,aside from size, are of similar construction, being each formed from apiece of wire which is' bent up and down to form a plurality of U-shapedbends as shown in Fig. 1, the whole being bent to form a split ring, asshown in Figs. 2 and 3. As will be seen from Fig. 1, the U- shaped bendsare also bent into bow-shape in the vertical plane, with the ends of thebends being engaged with the contacts 5 or 13, and the intermediate partengaging the contacts 6 or I! as the case may be. The endsof the U-shaped bends are slightly flattened to give greater bearing against thecontact onthe body.

The resilient members thus formed provide a very good electricalengagement between the contacts on the body and those on the cartridge,

are simple to make and easy to position.

What I claim as my invention is:

1. An electrical cut-out comprising a tubular body of insulatingmaterial, having a contact adjacent each end thereof; a fuse cartridgeslidable longitudinally within said body, said cartridge having acontact adjacent each end engaging the corresponding contact on thebody, the lower contact on the cartridge having a tubular extension,said extension being internally threaded for engagement by a cartridgeremoving tool, the threads being cut away at one side to form a ventgroove for the escape of gases from the interior of the cartridge, whensaid tool is in position.

2. An electrical cut-out comprising a tubular body of insulatingmaterial, having a contact adjacent each end thereof; a fuse cartridgeslidable longitudinally within said body, said cartridge having acontact adjacent each end eninternally threaded for engagement by a.cartridge removing tool;' said tubular extension having a bell-mouthedlower end forming a guide for the entrance of said tool.

3. An electrical cut-out comprising a tubular body ofinsulating'material, having a contact adjacent each end thereof; a fusecartridge slidable longitudinally within said body,.said cartridgehaving a contact adjacent each and engaging the corresponding contact onthe body, the lower contact on the cartridge having a tubular extension,said extension being internally threaded for engagement by a cartridgeremoving tool, the threads being cut away at one side to form a ventgroove for the escape of gases from the interior of the cartridge whensaid tool is in position, said tubular extension having a bell-mouthedlower end forming a guide for the entrance of said tool.

"4. An electrical cut-out comprising a porcelain body having a fusecartridge receiving bore formed therethrough; said body having. a hollowcontact of malleable cast metal mounted on each end thereof, theinterior of each of said contacts forming an extension of the bore ofthe body; each of said contacts having an integral annular flangesleeved on to .the adjacent end of the body, said flange adjacent itsedge being of gradually reduced thickness and said body having aperipheral recess into which the

